env-must-exist

Assert that environment variables are present. Fail fast in CI.

Problem: You deploy to production, but forgot to add DATABASE_URL to the dashboard. Your app crashes silently or in a weird way 5 minutes later. Solution: Add a pre-flight check script. If the var is missing, the deploy fails immediately with a clear error.

Install

npm install env-must-exist

Usage

CLI (Recommended for CI)

Add this to your build or start script:

{
  "scripts": {
    "build": "env-must-exist DATABASE_URL STRIPE_KEY && next build"
  }
}

If STRIPE_KEY is missing, you get:

❌ Missing required environment variables:
   - STRIPE_KEY

API

import { assertEnv } from 'env-must-exist';

assertEnv(['DATABASE_URL', 'API_KEY']);

License

MIT

{ github.com/mgks }